Would a real butcher block be going to far?

When you say old world butcher block are you talking about old growth European hardwood butcher block tips or American old growth maple? 

Keep in mind, work-a-day butcher blocks were never made for their resonance response to low end frequency and mass. It was built to withstand butchering.

You can get mass from kiln dried hardwoods and laminate accordingly but I doubt very much you will hear little difference. I've got a 25yo console I made from birch plywood and also had a solid heart pine cabinet I made. The former a piece of movable furniture, the other a solidly anchored built-in. The latter proved to be no better in sound quality. Both were utilized in a raised frame house vs  slab on grade.

The old butcher block, imo, is worth it for the story you can tell, not for the sound quality.

1" thick x 13" stone slabs on 2x6 framing with 4x6 posts on a concrete floor.

’Bout 6’ long, and I’d like to move it about 12" ’length-wise’.

However, I’d have to take everything off of it.

Remove the shelves (2); move frame.

Reverse the prior procedures.

Not a happening.

no.

Going with really thick B. Block will put you into the same quandary

Locate Carefully.

Rear guard, J

(aka, CYA)

I ordered custom made  (2 shade ) maple blocks from a guy on Etsy. I finished them myself with stain and poly and brass spiked feet for my vintage McIntosh MC30s. They turned out really nice and the whole project was fun to do. I also saved a lot of money. 

My TT rests on a new Boos 2" hard maple block perched on springs. FWIW, low frequency resonances have been reduced versus sitting naked on the rack shelf.

A while ago I bought a bamboo cutting board with the gravy groove around the perimeter. I filled in the groove with soft rubber (?) fishing worms to isolate the board. Flipped it over and put my integrated on it.  Worked like a charm.